There is an increasing public pressure to have seismic-resistant structures made with massive wooden panels such as Cross Laminated Timber (CLT). It is a well-known fact that the type and behaviour of the connections govern the overall seismic behaviour of the system. Thus, special attention must be paid to the connections when designing such buildings under lateral loads. Previous experimental studies showed that although CLT structures with conventional seismic detailing could survive the design level earthquakes, the extent of damage in connectors could be severe. Therefore, it is necessary to have resilient connection systems if a low damage performance is desired.
This paper presents the latest developments and design methods specially developed to use damage avoidance connection systems for mass timber structures. It also presents case studies of low damage mass timber structures where innovative and resilient connections are used instead of conventional high damage/pinching connectors to firstly, introduce energy dissipation to the structures (without damage), and secondly, provide a self-centring behaviour.
Two different case studies in Canada are presented and discussed. The case studies include the Yukon building (4-storey mass timber building) and Keith Drive building (10-storey mass timber building with rocking CLT core) in Vancouver, Canada. The design approach, design challenges and different aspects of erection/construction are discussed. The findings of this paper demonstrate great potential for low damage mass timber structures in high seismicity areas such as New Zealand and Canada. Furthermore, the conclusions of the paper give an insight to practitioners on how to design low mass timber structures that are not covered by the current standards or guidelines.